Tiny implantable medical devices with moving parts and drug chambers are a part of the future of medicine. Researchers at Columbia University have made a big step towards that by developing a new method for creating millimeter scale mechanisms out of hydrogels. Hydrogels are biocompatible, but they’re difficult to work with. The Columbia team developed an additive manufacturing technique to layer hydrogels to result in tiny devices that are biocompatible and have powered mechanisms such as pumps and rotors.
The technology is dubbed implantable microelectromechanical systems (iMEMS). One large achievement was the development of a “locking mechanism” that allows accurate control of the moving parts.
One device created using the iMEMS technique was tested in lab mice with cancer tumors. It had a capsule that slowly released a chemotherapy agent, and demonstrated high targeting of the tumors while sparing the rest of the body from high levels of toxicity.
Some details about how the devices are constructed according to a Columbia announcement:
The team used light to polymerize sheets of gel and incorporated a stepper mechanization to control the z-axis and pattern the sheets layer by layer, giving them three-dimensionality. Controlling the z-axis enabled the researchers to create composite structures within one layer of the hydrogel while managing the thickness of each layer throughout the fabrication process. They were able to stack multiple layers that are precisely aligned and, because they could polymerize a layer at a time, one right after the other, the complex structure was built in under 30 minutes.
Study in journal Science Robotics: Additive manufacturing of hydrogel-based materials for next-generation implantable medical devices…
Via: Columbia University…